This application claims benefit of the filing date of Japanese Patent Number 000139403.
(1) Field of the Invention
The present invention concerns a coordinates input method for a coordinates input device (i.e., digitizer or tablet) which detects the position of a position indicator by utilizing electromagnetic induction and then inputs it into a host computer.
(2) Description of Related Art
The electromagnetic induction format has been known with regard to coordinates input devices for computers, etc. in the prior art. Such a coordinates input device based on the electromagnetic induction format consists of a tablet on which multiple loop coils are configured and a coordinates indicator. Upon the retention and displacement of the coordinates indicator by an operator on a tablet, the concomitantly indicated position is detected by the tablet and then inputted into a computer of a higher order.
The coordinates indicators used for the tablet of the prior art based on the electromagnetic induction format will be explained with reference to FIGS. 4(a) and 4(b). FIG. 4 (a) is a diagram which shows a transparentized plane view of the internal structure of the tablet (420). FIG. 4 (b) is a diagram that shows a longitudinal cross-sectional view of the coordinates indicator (440). The coil (441), which the coordinates indicator (440) possesses, is driven by the oscillator (443) under the pervasion of an alternate current whose frequency is F1, resulting in the generation of a magnetic field. (444) signifies a battery that feeds an electric power into the oscillation circuit (443). The coordinates indicator is normally equipped also with a switch, etc. for obtaining information other than the coordinates value, although they are omitted from FIG. 4 in that they are not directly related to the present invention.
As FIG. 4 (a) indicates, a group of loop coils CX1, CX2, CX3, . . . CXm, which are extended along the longitudinal direction (i.e., longitudinally expansive), are configured along the lateral direction (i.e., X direction) on the tablet (420). Only CX1 and CXm are drawn in FIG. 4 (a) for avoiding convolutions. Another group of loop coils CY1, CY2, CY3, . . . CYn, which are extended along the lateral direction (i.e., laterally expansive), furthermore, are configured along the longitudinal direction. Only CY1 and CYn are drawn in FIG. 4 (a) for avoiding convolutions. The respective numbers of the concomitantly configured loop coil groups depend on the size of the tablet.
The switch (421) in FIG. 4 (a) is a switch for selecting one coil from a group of multiple members, and the coil which has been selected by said switch becomes connected to the signal detection circuit (422). The position of the coil (441) on the tablet (420) is calculated by the computation circuit (423) based on the output of the detection circuit (422). The calculated position is normally transferred to a host computer, etc., although the corresponding block is omitted from the figure. A battery or external power source, furthermore, is used as a power source, although it is omitted from the figure.
In a case where the operator has placed the coordinates indicator (440) on the tablet (420) discussed above, for example, the magnetic field which has been generated by the coil (441) of the coordinates indicator (440) induces a higher voltage in relation to a loop coil of the tablet coil group closer to the coil (441) and a lower voltage in relation to a loop coil farther from it. In a case where the respective induction voltages are detected by sequentially switching the coils of the tablet via the switch (421), therefore, the respective distributions shown in FIG. 6 (a) and FIG. 6 (b) can be obtained along the longitudinal and lateral directions. The longitudinal and lateral positions of the coil (441) on the tablet can be discerned by calculating their output values by using the computation circuit (423). The positions of the coordinate indicator (440) can therefore be discerned in a case where the coordinate indicator (440) is retained above the tablet by the operator, whereas in a case where it is displaced while being continuously retained, the coordinates on the line of displacement can be obtained.
Incidentally, cases where coordinates variation magnitudes (i.e., relative coordinates) are utilized by host computers instead of the direct utilization of the coordinates (i.e., absolute coordinates) are conceivable. In such a case, a coordinates indicator may be used in place of a mouse, which represents another type of input machine. In this case, the coordinates indicator of the tablet is often referred to as a xe2x80x9cpseudomouse.xe2x80x9d
In a case where the coordinates indicator of the tablet is utilized as such a pseudomouse, operative procedures identical to those for handling a mouse do not suffice, and therefore, slightly different operative procedures are imposed on the operator. This topic will be explained with reference to FIG. 5. Of said FIG. 5, the display contents of the display device (550) which are used for ordinary computers are shown in (a), whereas the movements of the coordinates indicator (540) above the tablet (520) are shown in (b). The tablet is normally used while being fixed to the top of a desk, whereas the coordinates indicator (540) is routinely operated while being held in the operator""s hand.
In the context of inducing the displacement of an indicated point on the display device (50), the coordinates indicator (540) must be displaced while being aligned against the coordinates axes of the tablet (520) (i.e., XY rectangular coordinates axes) regardless of the pervasion of an absolute coordinates system or relative coordinates system. In other words, to illustrate with reference to an easy-to-understand example, in a case where an attempt is made to induce a parallel displacement of the indicated point on the display device (550), the coordinates indicator (540) must also be displaced in parallel to the tablet while being positioned above said tablet. For this reason, the operator is forced to displace the coordinates indicator (40) while its disposition is being matched with that of the tablet, as a result of which unnatural hand movements may become required in some cases. In other words, the coordinates axes of the plane of the coordinates indicator (40) coincide with the coordinates axes on the tablet plane, and therefore, the coordinates indicator (40) must be displaced while its disposition is being aligned against the coordinates axes of the tablet plane.
In a case where an attempt is made to displace the indicated point (i.e., mouse pointer) from point A1 to point A2 on the display device (550), for example, it is necessary to displace the coordinates indicator (540) on the tablet from point B1 to point B2.
Regardless of the size disparity between the display device (550) and tablet (520), the dispositions of the respective coordinates axes of the display device (550) and tablet (520) are exactly the same, and therefore, a parallel displacement on the display device (550) is articulated by displacing the coordinates indicator (540) in parallel to the tablet (520) while being positioned above said tablet (520) as well. Even in the cases of non-parallel lines and curves, therefore, the coordinates indicator (540) must be displaced in compliance with the coordinates axes of the tablet (520).
One difference from the mouse operation method known in the prior art has been thus articulated. The mouse has no equivalency to the tablet (520). The mouse is therefore a machine which enables the input of a coordinates displacement magnitude in compliance with the coordinates axes of itself, namely the mouse.
The objective of the present invention is to provide a coordinates input method which is capable of solving the problem of the pseudomouse.
The following constitution is provided by the coordinates input method of the present invention in order to solve the problem cited above: In a coordinates input system which consists of a coordinates indicator, a tablet which detects the position indicated by said coordinates indicator, and a host computer which obtains the coordinates data outputted by said tablet, the following are orchestrated: A coordinates indicator information detection step at which, upon the retention and displacement of said coordinates indicator on said tablet by an operator, coordinates indicator information data which include the coordinates values of said coordinates indicator on said tablet before and after its displacement as well as the disposition of said coordinates indicator are detected by said tablet, a data transmission step at which said coordinates indicator information data which have been detected at said coordinates indicator information detection step are transmitted to said host computer by said tablet, and an indicator coordinates axis standard data acquisition step at which said coordinates indicator information is taken into said host computer and then utilized as data while each of the coordinates axes of said coordinates indicator is being designated as a standard.
In an alternative embodiment, a pair of coils for emitting an alternate magnetic field are configured on the aforementioned coordinates indicator while being mutually separated via a distance, whereas multiple loop coils for receiving the alternate magnetic field obtained from said coordinates indicator are configured on the aforementioned tablet, whereas the aforementioned coordinates indicator information detection at the aforementioned coordinates indicator information detection step is enabled by amplifying and computing the signals received by the aforementioned multiple loop coils and by thus obtaining the positions of said pair of coils within said coordinates indicator.
In another alternative embodiment, a pair of coils are configured on the aforementioned coordinates indicator while being separated via a certain distance, whereas the aforementioned tablet possesses multiple loop coils, whereas an alternate magnetic field is emitted toward said coordinates indicator from said multiple loop coils, whereas an induction current is generated based on an electromagnetic induction effect exerted on said pair of coils within said coordinates indicator by said alternate magnetic field, whereas the detection of the aforementioned coordinates indicator information at the aforementioned coordinates indicator information detection step is enabled based on the acquisition of the positions of said pair of coils upon the reception, amplification, and computation of a magnetic field generated under the pervasion of said induction current by said tablet.
In still another alternative embodiment, the data transmitted at the aforementioned data transmission step include coordinates data on the positions of the aforementioned pair of coils in relation to tablet coordinates axes, whereas the aforementioned indicator coordinates axis standard data acquisition step is implemented by converting the coordinates value of the aforementioned coordinates indicator in relation to the coordinates axes of said tablet into the displacement magnitude of the coordinates indicator in relation to the coordinates axes of said coordinates indicator based on a routine ascribed to a software program memorized into a memory of the aforementioned host computer.